Abstract: Disclosed is a method for forming lithium hexafluorophosphate by reacting together phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent and then making the reaction product formed in the solvent react with hydrogen fluoride. This method is characterized by that a lithium hexafluorophosphate concentrated liquid is obtained by conducting a filtration after making the reaction product formed in the solvent react with hydrogen fluoride and then subjecting the filtrate to a concentration by degassing. By this method, it is possible to easily produce a high-purity, lithium hexafluorophosphate concentrated liquid at a low cost.

Abstract: There is provided a method for producing an electrolyte solution for lithium ion batteries, in which lithium hexafluorophosphate is used as an electrolyte, comprising the steps of (a) reacting phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent; and (b) reacting a reaction product of the step (a) formed in the solvent, with hydrogen fluoride.

Abstract: Disclosed is a method for forming lithium hexafluorophosphate by reacting together phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent and then making the reaction product formed in the solvent react with hydrogen fluoride. This method is characterized by that a lithium hexafluorophosphate concentrated liquid is obtained by conducting a filtration after making the reaction product formed in the solvent react with hydrogen fluoride and then subjecting the filtrate to a concentration by degassing. By this method, it is possible to easily produce a high-purity, lithium hexafluorophosphate concentrated liquid at a low cost.

Abstract: Disclosed is a method for producing a lithium ion battery electrolyte solution containing lithium hexafluorophosphate as an electrolyte and a lithium ion battery using the electrolyte solution. The electrolyte solution is produced by reacting lithium chloride with phosphorus trichloride and chlorine in a non-aqueous organic solvent, reacting a reaction product generated in the solvent with hydrogen fluoride, reacting unreacted remaining hydrogen fluoride with lithium chloride, and then, separating the resulting reaction solution by filtration into a filtrate and a solid residue. The filtrate is obtained as the lithium ion battery electrolyte solution. The solid product is further reacted with phosphorous trichloride and chlorine in a non-aqueous organic solvent. The reaction product generated in the solvent is reacted with hydrogen fluoride, followed by reacting unreacted remaining hydrogen fluoride with lithium chloride.

Abstract: A method for producing an electrolyte solution for a lithium ion battery involving reacting a lithium halide selected from the group consisting of lithium fluoride, lithium chloride, lithium bromide, lithium iodide and a mixture of at least two of these, with phosphorus pentachloride and hydrogen fluoride in a nonaqueous organic solvent, thereby producing lithium hexafluorophosphate as an electrolyte of the electrolyte solution.

Abstract: There is provided a method for producing an electrolyte solution for lithium ion batteries, in which lithium hexafluorophosphate is used as an electrolyte, comprising the steps of (a) reacting phosphorus trichloride, chlorine and lithium chloride in a nonaqueous organic solvent; and (b) reacting a reaction product of the step (a) formed in the solvent, with hydrogen fluoride.

Abstract: There is provided a method for producing an electrolyte solution for lithium ion battery, which is characterized in that lithium fluoride, lithium chloride, lithium bromide, lithium iodide or a mixture of any of these is reacted with phosphorus pentachloride and hydrogen fluoride in a nonaqueous organic solvent, when an electrolyte solution for lithium ion battery, which contains lithium hexafluorophosphate as an electrolyte, is produced.